At this strategic site, controlling the crossing of the River Trent, a manor house has existed since at least the thirteenth century. Once owned by the important Percy family, it passed to the Burgh family on the marriage of Elizabeth Percy to Thomas Burgh of Yorkshire in 1430. It was their son Thomas who built the present house.

From surviving written records, scientific evidence such as dendrochronology
and stylistic comparison, the dating of the huge manor house at Gainsborough can be confidently placed at between 1465 and 1500. The earliest parts are the magnificent Great Hall and its adjoining kitchen block, with the wings and tower slightly later. As with any building of this age, its fortunes have waxed and waned along with its owners and the prevailing political and economic conditions.

When Gainsborough was first built by Sir Thomas, first Lord Burgh, the Great Hall was a place for feasting and entertaining. The roof was constructed from naturally curved oak beams, with no tie beams to detract from the graceful proportions. The original wooden louver which let smoke out from the fires and braziers was removed for safety reasons but is now on display inside an upper room.

At one end of the Great Hall are three small doorways which lead to the kitchen, serving and storage areas. These would originally have been hidden from the Lord's sight by a Screens Passage and where it once joined the walls, traces remain. Through the doors are the Buttery, where wine and ale was stored, the Pantry, where cold cooked food (such as bread) was stored and taken through to the Hall and a Servery between the Kitchen and the Great Hall. The Servery has two huge hatches, which originally had wooden shutters and it was from here that the food was passed through and brought to the table by the upper servants, who were often younger sons of noble families. The Kitchen itself is huge, capable of the catering requirements of an important household like Lord Burgh's, even when visitors such as Richard III came in 1483.

At the opposite end of the Great Hall from the Kitchen Block, a carved stone window rises to the roof, letting light in at the important end of the room and also proclaiming the wealth and status of the Lord, being able to afford glass at the end of the fifteenth century.

The private apartments of the Lord's family were reached off the Lord's end of the Great Hall. The original Solar has been altered in modern times beyond recognition, but is now furnished to give an idea of its original use and appearance. The East Wing, leading off from the Staircase Gallery, is a wooden framed structure built shortly after the Great Hall, probably around 1475. At this time, Sir Thomas was rising in political importance both locally in Lincolnshire and at Court. He was in favour after having helped King Edward to escape from Middleham Castle in 1469 and managed to keep in favour with the succession of kings through to Tudor times. To consolidate and maintain his position, a suitable home for entertaining and display was required and Thomas' enlarged building at Gainsborough was just the thing. On the first floor is a large room, the ceiling having been raised by the Victorians and the room used as Gainsborough's ballroom, it is now furnished in the Victorian style, but this remains the original Upper Great Chamber of Sir Thomas' day. The bay windows (see below) were added as part of a late Elizabethan improvement to this wing, when the external brickwork was also added to bring the building's appearance up to date. The Tower on the right of the picture dates from between 1470 and 1490 and was designed for comfort and display, not defence. The winding stairs are built into one turret and the other contains garderobes.

The West Wing, forming an open-sided courtyard with the Great Hall and the East Wing, was built to provide further accommodation and is constructed from four timber-framed bays. No links were built directly into the Buttery end of the Great Hall for security purposes. This wing has twelve fireplaces and twelve garderobes built into the west side, adding to the comfort of guests and family members. Originally there were four separate suites in this wing, the top floor forming one which was linked by a long corridor. Access to this top suite was by an outside staircase. At a later date, corridors and doors were cut through, joining the separate accommodations together.

The Burgh family's fortune waned during Elizabeth I's reign. The fifth Lord Burgh, Thomas, was prominent in the campaigns in the Low Countries and he was stationed there for a considerable length of time, reducing his health and his ability to manage Gainsborough and his estates in England. He died in Ireland in 1597 and left his wife and young children in financial hardship. Just before his death, the manor of Gainsborough had been sold to William Hickman, to help meet the family debts. He reflected a change in the social make-up, the trend for old money families to decline and a new rich merchant class to take over their property.

William Hickman offered support to the Separatist congregation at Gainsborough and many who worshipped at the Old Hall formed part of the Pilgrim group which emigrated to America on the Mayflower. During his ownership, William made repairs and alterations to the building including a new brick front to the east face of the east wing and the south face of the west wing. Panelling was put in and a mural was painted in the lower great chamber.

William's son, Willoughby, was created Baron Gainsborough by Charles I in 1643, the same year of the Battle of Gainsborough during the Civil War. Much of the surrounding town was destroyed during the battle and Willoughby was fined £1000, about a sixth of his income, by Parliament. Having survived the Civil War, the Hickmans continued to prosper and successive family members became local Members of Parliament. The fourth baronet built a new, large house at Thonock on the outskirts of Gainsborough in 1720 and the Old Hall's decline commenced.
Lord Abingdon rented the east wing for some years and the great Methodist reformer John Wesley preached here on several occasions. The Old Hall was then used as a coarse linen factory in the second half of the eighteenth century and when that failed, the Great Hall became a theatre in 1790. The necessary alterations damaged the architecture, but the theatre was very popular and continued until 1848. Various other parts of the building were divided up into tenements and lived in by different families. A descendant of the Hickman family, Sir Hickman Beckett Bacon, repaired the Old Hall in the 1840's and it passed from the Bacon family into the joint responsibility of English Heritage and Lincolnshire County Council.